*Reading this on mobile may cut off the charts. There is a lot of data and it is too wide. If you want to read it all please use a tablet but a computer is best. Sorry.
Lets take what I discussed in my last post and apply it to the top MLB players. I looked at the top 5 hitters from 2018 in barrels. Then we will look at their average exit velo and compare it to optimal expected velo and find the data point that matches. I want to point out that this is not an exact and I am probably wrong. But its worth looking into and analyzing. I am sure we are close but there are variables that can’t be accounted for. We are just looking at averages and more specifically, average line drives and fly balls.
- We don’t know pitch speed but we can take the MLB average fastball at 92.8 mph.
- We don’t know the pitch
- We don’t know hit direction
If you need things defined, please read my previous post http://caphitting.juxt.media/baseball-bat-ball-collision-using-blast-diamond-kinetics-and-hit-trax-how-can-we-use-data-for-bat-fittings/
- 1.2 0.2 Exp = Is what the optimal exit velo should be based on bat speed and pitch speed. = 1.2 x bat speed + 0.2 x pitch speed
- Opt Bat/Exit = Optimal ratios
Players Data
| Max Exit | Avg Exit | FB LD Avg | GB Avg | |
| Joey Gallo | 117.50 | 93.9 | 99.8 | 85.200 |
| Khris Davis | 112.80 | 92.4 | 97.1 | 87.500 |
| JD Martinez | 116.70 | 93 | 96.7 | 89.200 |
| Mookie Betts | 110.60 | 92.3 | 95.9 | 88.800 |
| Ryan Zimmerman | 110.80 | 92.6 | 97.8 | 89.000 |
Optimal Reference Chart – Based on MLB avg fastball
| Bat Speed | Pitch Speed | 1.2 0.2 Exp | Opt Bat/Exit |
| 62 | 92.8 | 92.96 | 1.499 |
| 65 | 92.8 | 96.56 | 1.486 |
| 68 | 92.8 | 100.16 | 1.473 |
| 72 | 92.8 | 104.96 | 1.458 |
| 76 | 92.8 | 109.76 | 1.444 |
| 79 | 92.8 | 113.36 | 1.435 |
| 82 | 92.8 | 116.96 | 1.426 |
| 85 | 92.8 | 120.56 | 1.418 |
The average FB LD exit velo for the above 5 hitters is 97.46 MPH. To match that to an optimal expected velo we find that the average bat speed is around 66 mph which is 97.79 mph and a 1.481 ratio (66 mph bat speed is not in the above chart).
Can we trust this data?
I think its close. I have worked with an MLB hitter who has a bat speed in the 80s off a tee and it drops to the upper 70s for flips. When facing a machine at 70 mph from 45′ his bat speed was in the 73-77 mph range. He could get into the upper 70s and then 80s if he went after it but he said he wouldn’t ever swing that hard in a game. This still looked like a controlled swing though.
So if we take the above MLB hitter that has power and know that on a 70 mph machine he can swing in the 73-77 mph range then if we assume a 92.8 mph pitch coming in without it being grooved over the plate like a machine does could be in the upper 60s range. I don’t think that’s a far stretch to assume. I do think its possible that hitters in certain counts or sitting on certain pitches can unleash a 75-80 mph bat speed and crush a pitch. This is where the 110 + mph home runs happen. Perfect contact on a fast bat speed in the right location. Those numbers actually agree with my findings as well.
Bryce Harper’s Monster Home Run
Lets apply this to an actual home run by Bryce Harper. This was on 7/2/2018. 2-0 count and he unleashed on the ball. I don’t think he held anything back here. The pitch was 97.6 mph and the exit velo was 112.1. Lets assume he made optimal contact.
https://www.mlb.com/video/statcast-harpers-439-ft-hr/c-2224391083
| Bat Speed | Pitch Speed | 1.2 0.2 Exp | Opt Bat/Exit |
| 68 | 97.6 | 101.12 | 1.487 |
| 72 | 97.6 | 105.92 | 1.471 |
| 76 | 97.6 | 110.72 | 1.457 |
| 77 | 97.6 | 111.92 | 1.454 |
| 78 | 97.6 | 113.12 | 1.450 |
| 79 | 97.6 | 114.32 | 1.447 |
| 82 | 97.6 | 117.92 | 1.438 |
| 85 | 97.6 | 121.52 | 1.430 |
It looks like he had a bat speed of 77.5 mph.
Another Harper Home Run
Pitch 90 and Exit Velo 112.4 = Bat Speed 79 mph
| Bat Speed | Pitch Speed | 1.2 0.2 Exp | Opt Bat/Exit |
| 68 | 90 | 99.6 | 1.465 |
| 72 | 90 | 104.4 | 1.450 |
| 76 | 90 | 109.2 | 1.437 |
| 77 | 90 | 110.4 | 1.434 |
| 78 | 90 | 111.6 | 1.431 |
| 79 | 90 | 112.8 | 1.428 |
| 82 | 90 | 116.4 | 1.420 |
| 85 | 90 | 120 | 1.412 |
Another Harper Home Run
Pitch 87 and Exit Velo 108.6 = Bat Speed 76 mph. This was offspeed, not sure of the pitch but here is where spin matters and pitch matters. You see how far he hit the ball with only a 108.6 exit velo. This is where you hear MLB hitters talk about reversing the spin on breaking balls.
| Bat Speed | Pitch Speed | 1.2 0.2 Exp | Opt Bat/Exit |
| 68 | 87 | 99 | 1.456 |
| 72 | 87 | 103.8 | 1.442 |
| 76 | 87 | 108.6 | 1.429 |
| 77 | 87 | 109.8 | 1.426 |
| 78 | 87 | 111 | 1.423 |
| 79 | 87 | 112.2 | 1.420 |
| 82 | 87 | 115.8 | 1.412 |
| 85 | 87 | 119.4 | 1.405 |
Aaron Judge – Not every hit is a home run
Pitch 97. Exit Velo 118.1. Bat Speed 82 mph.
| Bat Speed | Pitch Speed | 1.2 0.2 Exp | Opt Bat/Exit |
| 68 | 97 | 101 | 1.485 |
| 72 | 97 | 105.8 | 1.469 |
| 76 | 97 | 110.6 | 1.455 |
| 77 | 97 | 111.8 | 1.452 |
| 78 | 97 | 113 | 1.449 |
| 79 | 97 | 114.2 | 1.446 |
| 82 | 97 | 117.8 | 1.437 |
| 85 | 97 | 121.4 | 1.428 |
Josh Donaldson
Pitch Speed 93. Exit Velo 109.5. Bat Speed 75 mph.
| Bat Speed | Pitch Speed | 1.2 0.2 Exp | Opt Bat/Exit |
| 68 | 93 | 100.2 | 1.474 |
| 72 | 93 | 105 | 1.458 |
| 76 | 93 | 109.8 | 1.445 |
| 77 | 93 | 111 | 1.442 |
| 78 | 93 | 112.2 | 1.438 |
| 79 | 93 | 113.4 | 1.435 |
| 82 | 93 | 117 | 1.427 |
| 85 | 93 | 120.6 | 1.419 |
Conclusion
I guess we can go over every home run and play with this but its showing accurate that Bryce Harper has an upper 70s bat speed. Aaron Judge has a lower 80s bat speed. Josh Donaldson has a mid 70s bat speed. If we really wanted to get technical we could look at every home run Harper hit in 2018 and break it down then average everything out. Where I am more interested is in seeing the quality of contact and instead of us using barrels as best quality we can get more detail and start to look at optimal contact for each player. Its easier for Judge to barrel at his swing speed vs Donaldson. But does that mean that Donaldson has more “skill” if he can create the same number of barrels? Now we can look at actual skill vs raw power.
I’m sure we will break more swings down over the next season. This is fun.